Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!bloom-beacon!kelly.UUCP!marvin
From: marvin@kelly.UUCP (Kyle Marvin)
Newsgroups: comp.windows.x
Subject: Multiple Screens and Pointer Tracking?
Message-ID: <8909152100.AA07252@kelly.>
Date: 15 Sep 89 21:00:40 GMT
Sender: daemon@bloom-beacon.MIT.EDU
Organization: The Internet
Lines: 40

I am currently working on a multiple screen server implementation and
have some questions on the best way to handle pointer tracking.  Each
screen will be displayed on a separate monitor, and I'm wondering how
to handle the movement of the pointer between screens.  My first
assumption is that the desired behavior is to have it appear to the
user as if the two monitors are contiguous as the pointer moves
between them (i.e. as it moves off the left side of Screen 1, it
appears on the right side of Screen 0, and vice versa).  If I'm wrong
there, flame now and offer your own suggestion :-{)

Given that, the real rub comes in deciding how the coordinate space of
the pointer maps to the display space.  Is Screen 0 to the left,
right, top, or bottom of Screen 1?  The display capabilities of the
two screens are very different and so it could be desirable for the
different user to physically place them at different orientations from
each other (any budding young human factors guys out there care to
explain why?).

My question is not so much how to implement this, but rather what is
appropriate interface?  The way I see it, the following are possible:

	1) No interface.  Screen 0 is always assumed to be at a fixed
	   orientation from Screen 1.  Blech!

	2) Provide options such as "-top", "-bottom", "-left", or "-right"
	   to specify the orientation of Screen 1 relative to Screen 0
	   at server startup.  (But what about 3 screens...).

I'd be interested to hear from anyone else who's worked with/on a
multiple screen server or just has a strong opinion on the subject.
I'd like to be consistent with what has already been done elsewhere if
possible.  Perhaps Santa Claus might bring an early present about what
to expect in R4...

Thanks In Advance,

Kyle W. Marvin
Visual Information Technologies, Inc. (VITec)
3460 Lotus Drive 	Plano, TX 75075 	(214) 596-5600
uunet!convex!vitsun!marvin